1. Option A. Temperature and Salinity
2. Option D. (I think)
3. Option D.
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(3.5mol)(24.106 g/1mol c6h6) =84.371 g C6H6
Stable isotopes are not radioactive nor dangerous.
Unstable isostopes are radioactive and have different mass of the element.
Answer:

Explanation:
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In this case, since a dilution process implies that the moles of the solute remain the same before and after the addition of diluting water, we can write:

Thus, since we know the volume and concentration of the initial sample, we compute the resulting concentration as shown below:

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